Blue Signal
Blue Signal is Rivet Reach's ON / OFF automation network. Use it to switch machines, pulse controls, show a status light, automate tank valves and react to tank fill levels.
Blue Signal carries instructions, not power. Electricity, item transport, fluid transport and signal are separate channels. A signal can tell a machine to run, but it does not supply the electricity, items or fluid that machine needs.
The machinery below is using Rivet Reach's real pipe/channel system. Fluid, power and Blue Signal can follow the same transport-pipe route, but each remains an independent network.
The easiest first test is a Lever → Signal Wire → Signal Indicator circuit.
 Lever ON / OFF |
→ |
 Signal Wire carries the state |
→ |
 Signal Indicator shows the state |
- Place a Lever.
- Place a Signal Indicator nearby.
- Join them with Signal Wire.
- Use the Lever once: it stays ON until you use it again.
- The Signal Indicator should follow the same state.
The Signal Indicator does not need electrical power. It is a simple visual signal output, which makes it useful for testing a circuit before connecting machinery.
If your route needs to turn vertically, use Signal Conduit instead of ordinary Signal Wire.
| In-game part | What it does |
|---|---|
|
Signal Wire |
Carries Blue Signal horizontally. Use it for simple flat runs. |
 Signal Conduit |
Carries Blue Signal through all six directions, so it can route vertically as well as horizontally. It is also the item consumed when fitting a signal channel to a transport pipe in Survival. |
 Signal Relay |
Directional signal part: rear input → front output. The output changes one simulation tick after the input. |
|
Lever |
Manual latched control. Use it once for ON and again for OFF. |
 Button |
Manual momentary control. Sends an ON pulse for one second, then returns to OFF automatically. |
|
Signal Indicator |
Visual output that shows the current signal state. It does not require electricity. |
For a normal controllable machine, the pattern is:
Control → Signal Wire / Conduit → machine's front signal input
A Pump, Crusher, Drill or Workshop Lamp is allowed to operate with no signal attached when its other requirements are satisfied.
Once a signal is attached:
- OFF disables the machine.
- ON permits the machine to operate.
- Electricity is still supplied through the machine's separate power connection.
This means adding Blue Signal gives you control without making signal wiring mandatory for every basic machine.
Use a Lever when you want the machine to remain enabled or disabled until you change it again.
Use a Button when you want a short trigger. Its signal lasts one second, so seeing it return to OFF immediately afterward is normal behaviour.
Signal Wire is the simple option for horizontal runs.
Signal Conduit can connect through all six directions. Use it when a circuit needs to climb, drop or route through a more complex factory layout.
A Signal Relay is directional:
REAR INPUT → RELAY → FRONT OUTPUT
+1 tick
Place it facing the direction you want the signal to travel. A state received at the rear appears at the front one simulation tick later.
That tiny delay is intentional, not lag or a broken connection.
Item Pipes and Fluid Pipes can carry extra fitted channels alongside their normal transport route.
Right-click the pipe centre or use Interact to open it, then choose:
- FIT SIGNAL to add a Blue Signal channel.
- FIT POWER to add an electrical channel.
In Survival:
- fitting signal consumes 1 Signal Conduit;
- fitting power consumes 1 Power Cable.
The fittings are separate from the Wrench, which changes item/fluid direction at a machine-facing end. See Pipes for input/output arrows and examples.
A pipe may have both fittings at the same time.
A fitted pipe can visually share one route for fluid/items, Blue Signal and electricity, but the three channels remain completely independent. Plain Item Pipe and Fluid Pipe carry neither signal nor electricity until the corresponding fitting is installed.
Each fitted channel follows its own real connections, so adding or removing a transport branch does not magically connect unrelated signal or power networks.
Multiblock tanks add two Blue Signal components that behave differently from ordinary machines.
A Tank Signal Valve Port is fail-closed: it requires an attached ON signal before fluid can pass.
- Enable the valve port and connect a Fluid Pipe on an accessible face.
- Hold a Wrench and right-click the valve-facing pipe end to select blue Input or red Output.
- Connect Blue Signal to the valve's keyed signal fitting.
- Send ON to open it.
- OFF or no attached signal keeps it closed.
This is different from machines such as the Pump or Crusher, which are allowed to operate when no signal is attached.
A Tank Level Sensor is a signal source. Set its percentage threshold and it outputs ON when the tank's stored liquid reaches that level.
That makes circuits such as this possible:
Tank Level Sensor → Signal route → Indicator / Relay / controlled system
See Build a multiblock tank for the tank-side construction rules.
These are shapeless recipes: ingredient positions do not matter. The grid size shown is the minimum crafting grid required by the recipe.
| Part | Grid | Ingredients | Output |
|---|---|---|---|
|
Signal Wire |
4×4 | Copper Wire ×1 + Azure Crystal ×1 | ×4 |
|
Signal Conduit |
4×4 | Copper Plate ×2 + Signal Wire ×1 | ×2 |
|
Signal Relay |
4×4 | Signal Conduit ×2 + Azure Crystal ×1 + Iron Plate ×1 | ×1 |
|
Lever |
3×3 | Stick ×1 + Cobblestone ×1 + Azure Crystal ×1 | ×1 |
|
Button |
3×3 | Stone ×1 + Azure Crystal ×1 | ×1 |
|
Signal Indicator |
4×4 | Glass ×1 + Azure Crystal ×1 + Copper Wire ×1 | ×1 |
The 4×4 recipes require the larger crafting grid used by the Machinist's Bench. Lever and Button can be made with a 3×3 grid.
Lever → Signal route → Workshop Lamp / Pump / Crusher / Drill
Use the Lever as a persistent master enable/disable control. Remember that each machine still needs its normal power and material inputs.
Button → Signal route → controlled input
The Button supplies a one-second pulse instead of remaining latched ON.
Tank Level Sensor → Signal Wire / Conduit → Signal Indicator
Set the sensor threshold to the fill level you care about. The indicator gives you a simple visible status without needing electrical power.
A Fluid Pipe can be fitted with signal so the fluid route and control route can travel together:
Fluid Pipe: water channel ───────────────→ valve nozzle
Blue Signal fitting ─────────→ valve signal fitting
They share the physical pipe route but are still separate networks.
| Symptom | What to check |
|---|---|
| Nothing reacts to the Lever | First test the route with a Signal Indicator. Check that the signal reaches the receiver's correct signal connection rather than its power, item or fluid connection. |
| The Button turns itself OFF | Correct behaviour. A Button only sends a one-second pulse. Use a Lever if you need a persistent ON state. |
| The Relay seems one step late | Correct behaviour. A Relay deliberately delays its rear input by one simulation tick before sending it from the front. |
| A flat wire route cannot climb vertically | Use Signal Conduit for six-direction routing. Signal Wire is horizontal. |
| A machine runs even though I did not wire a signal | Normal for Pump, Crusher, Drill and Workshop Lamp. No attached signal means signal control is optional; attach a signal if you want to gate operation. |
| A Tank Signal Valve stays closed with no signal | Normal. The valve requires an attached ON signal. Also confirm the port is Enabled and the adjoining pipe end has the required direction, set using a held Wrench. |
| A fitted transport pipe carries fluid/items but not signal | Open the pipe and confirm FIT SIGNAL has actually been installed. A plain Item Pipe or Fluid Pipe does not carry Blue Signal. |
| The machine has ON signal but still will not run | Blue Signal is only permission/control. Check the machine's separate electrical supply and its normal item/fluid requirements. |
| Signal and power share the same fitted pipe but one is disconnected | Expected if their connection shapes differ. Signal, power and transport each follow their own actual network connections. |
The easiest rule to remember is:
- Blue Signal = should this happen?
- Electricity = does it have energy to happen?
A Workshop Lamp is a good example: it needs electricity to produce light, while Blue Signal can optionally tell it whether it is allowed to turn on.
For generators, cables, batteries and battery banks, see Electricity and batteries.
Blue pipe arrows indicate Input into a machine; they are separate from Blue Signal. A wrench changes transport direction only and does not toggle the signal. Read Pipes for the full connection guide.